Simulacra,
When I bought the Sealskins, they were marketed as waterproof. But they looked like they were made of divesuit material. The raim water soaked through completely, as if I were wearing a porous but nonabsorbent glove, and probably was. What attracted me was the very flexible material, which made the gloves much more pleasant to wear.
They may have much better products now. If you can get to a gear store, try blowing though the material. If you can, water probably can too. Also look for flexible material (along with a good fit of course) for the obvious reason that they will function much better.
Suggest searching for waterproof gloves on BPL, rather than sticking to one brand. You will probably find a thread where the posts evaluate how waterproof different brands are. And you’l have the benefit of access to experiences of more users. A bit more work, though.
P.S. Was hiking in early winter/late fall, when the temp was often below freezing. Was laying out, clearing and marking a trail, a lot of physical work, and a lot of contact with tools. tree limbs. branches and brush. In other words, wanted something to protect my hands. Got caught in a light, but constant freezing rain, you could call it a constant drizzle. With the water soaking through the gloves, my hands eventually got numb, although the exertion slowed it down. Was afraid the hands would freeze. Did not get frostbite, but got plenty frosted with the Sealskinz gloves.
With the developments in waterproof breathable materials that are flexible; nowadays, you might be able to find what you are looking for.